Universal air conditioner



July 3, 1962 Filed July 1o, 1958 N. A. PENNINGTON UNIVERSAL AIR CONDITIONER 4 Sheets-Sheet l JNVENTOR, NEAL A. PENN/hierom www July 3, 1962 N. A. PENNINGTON UNIVERSAL AIR CONDITIONER 4 Sheets-Sheet 2 Filed July lO,v 1958 INVENToR,

NEAL APENN/NGTON. BY Www July 3, 1962 N. A. PENNINGTON v 3,042,383

UNIVERSAL AIR CONDITIONER Filed July 1o, 1958 4 sheets-sheet :s

IN VEN T 0R, NEAL A. PENN/NGTON.

,www

July 3, 1962 N. A. Pl-:NNINGTON 3,042,383

UNIVERSAL AIR CONDITIONER Filed July lO, 1958 4 Sheets-Sheet 4 80j- Jig-8l INVENTOR, NEAL ldf'fNlsllNn-ON.

B37., MQW Www/7 United sans,

My invention relates to new and useful improvements in air-conditioning apparatus, and more particularly to apparatus for universal (i.e., both summer and winter) air-conditioning. The present application is a continuation-in-part, as to all common subject matter of mycopending application No. 122,322, filed October 19, 1949, now abandoned. n

In my Patent No. 2,464,766, issued March 15, 1949, I disclosed the basic idea of all my systems, namely evaporatively'cooling a stream of outgoing air, and then transferring to that stream the heat from a stream of incoming air. Also therein I disclosed rand claimed a marked improvement on that general idea, namely the utilization, for the above-mentioned heat-transfer, of a flat cylindrical pad of metal-wool, divided into sectors, and rotating in the two streams. This heat-transfer means, which involves practically perfect counter-flow, is claimed per se in that patent; and the heat-transfer pad per se is claimed in a copending divisional (Serial No. 55,594, filed October 20, 1948, now Patent No. 2,563,415) of that patent. subsequent pending applications of mine.

-A second variant disclosed and claimed in the first mentioned patent, and several furtherr variants disclosed and claimed in copending applications of mine, are designed to increase the efficiency and reduce lthe pad` thickness of my basic apparatus.

My copending Patent No. 2,499,411, issued March 7, 1950, discloses and claims a novel thermostatic control, devised primarily for said apparatus, but adapted to use in other air-conditioning systems. l

Ever since the demonstration of the practicality, eiliciency, and commercial success of my `basic apparatus, one of my objectives has been to devise a universal airconditioner, utilizing insofar as possible the basic ideas and elements of that apparatus, with as little as possible change from and/ or addition to that apparatus.

My copending application, Serial No. 765,554, filed `August l, 1947 (now abandoned Without prejudice to two continuations-in-part: Serial No. 234,301, filed lune 29, 1951, and Serial No. 234,800, tiled July 2, 1951, now Patents Nos. 2,700,537 and 2,723,837), represents a successful solution of that problem; but the main object of the invention described and claimed in this present application is to attain a simpler and more efficient solution.

In addition to devising a universal air-conditioner based upon the basic apparatus of my Patent No. 2,464,766, my furthervobjects are to humidify the incoming air in winter, and to recirculate in winter. none or lvery little of the air, while conserving practically all of the heatof the discarded stale air. i

I shall take as the summer air-conditioner which I shall use as an exempliiication of the device which my present invention is intended to convert into a universal aire conditioner for winter as well as summer, the particular form of my basic apparatus which is shown in my copending Fatent No. 2,499,411, already referred to. Accordingly it will be among the objectives of this present invention: to utilize for winter air-conditioning the thermostatic controls of that application, without any alteration of their original summer setting, and without the rerouting of any of the air-streams; to utilize for winter air-conditioning the same heat-transfer means as in summer, without alteration or rerouting of air; and to utilize lfor humidfying the incoming winter air, the same elearent This system underlies all it@ e ments used to evaporatively cool the outgoing air in summer, still without alteration or rerouting. Furthermore I aim that such elements and controls as I may add for winter use shall remain connected in summer, with no alterations in setting.

Thus I shall have produced a universal air-conditioning apparatus which will operate all the year round, without vany switch-over, disconnection, or change of setting.

In addition to the objects above stated, Ihave worked out a number of novel and useful details, which will be readily evident as the description progresses.

My invention consists in the novel parts and in the combination and arrangement thereof, which are defined in the appended claims, and of which several embodiments are exemplified in the accompanying drawings, which are hereinafter particularly described and eX- plained. f

Throughout the description the same reference number is applied to the same member or to similar members.

FIGURE 1 is a vertical longitudinal section of a first variant of my present invention.

FIGURE 2 is a vertical longitudinal section of a second variant.

FIGURE 3 is a vertical longitudinal section of a third, variant.

FIGURE 4 is a vertical longitudinal section of a fourth.l variant.

FIGURE 5 is a vertical longitudinal section of a fifth variant. Y

FIGURE 6 is -a wiring diagram of one way of controlling my second variant.

FIGURE 7 is a Wiring diagram of one way of controlling my rst, third', fourth and fifth variants.

Let us now consider the first variant 'of my present invention, which rst lvariant is exemplified by FIGURE l.

Referring to FIGURE 1, we see that 31 is the main. container of my invention, in which 32 is an air-inlet from outdoors, 33 is a centrifugal fan, which impels incoming "air into passages 34, and thence through the upper portion of rotating heat-transfer pad 35. This pad 35 is similar to the corresponding pad of my Patent No.

(2,464,766, and is more particularly described in my copending application, Serial No. 55,594, tiled October 20,

v1948, now Patent No. 2,563,415, and contains a packpasses into the enclosure 39, through passage 40` and louvers 41.

Outgoing air passesfrom enclosure 39 through louvers N42 into passage 43, where it encounters evaporative pad 44, which serves exactly the same purpose as the corresponding pad of my said Patent No. 2,464,766. This pad 44 is kept moistened by pump 45 drawing water from tank 46 through pipe 47, and delivering this Water through pipe 48 to trough 49, whence the water seeps down through pad 44. So much of this water as does not evaporate into the outgoingr air during the waters downward u seeping through pad 44, is collected in trough 50, and

thence passes through pipe 51 back into tank 46 again. Pump 45 can be driven by an electric motor 52, or otherwise.

Evaporative pad 44 could be of any other convenient type, such for example as the rotating evaporative-pad of my said Patent No. 2,464,766; or any other convenient Patented July 3, 1962 f evaporation cooling means could be employed at this stage of my apparatus.

The outgoing air, having been evaporatively cooled in evaporative pad 44, cools heat-transfer pad 35, and then is sucked by `centrifugal yfan 53 into air-outlet 54 through which it is discharged outdoors or into the attic.

As already stated, the thus-cooled heat-transfer pad serves to Ianhydrously cool the incoming air.

Motor 55 drives shaft 56 through pulley 57, belt 58, and pulley 39. Shaft 56 drives the two fans 33 and 53 at a high rate of speed. Also, through gear-reduction 60, shaft 56 drives shaft 61, and thereby shaft 62, at about 30y r.p\.m., thus driving heat-transfer pad 35 (keyed to shaft 62) at that same rate.

Tank 46 is kept lled, from any convenient source (not shown) by means of ball-cock 63.

Thermostat 65, as in my alreadyamentioned copending Patent No. 2,499,411, is so connected to pump-motor 52, as to turn pump 45 on when the room temperature rises t to a predetermined high, and to turn the pump off again when the room temperature drops to a predetermined low.

Thus far I have been describing merely the basic apparatus of my prior inventions.

To convert this summer-time apparatus into a yearV 'round apparatus, I have added an air-heating device of any conventional or other type, together with 'appropriate thermostatic and hurnidistat controls for turning this device on and off. I shall call the air-heating device the beaten As shown in FIGURE 1, the heater takes the form of an electric grid `64, located across the incoming air-stream in passage 40. Thermostat `65, Vshownlocated in enclosure 39 (but could be located between heater 64 and louvers 41, or between louvers 4Z and evaporative pad 44) in addition to continuing to perform in winter without change its summertime function of turning pump 45 on and olii, is also so connected to heater 64 as to turn that heater on when the room-temperature drops to another or the same predetermined 10W; 'and to turn heater 64 off again when the room-temperature rises to another or the same predetermined high. When in the claims as to any of my five variants I recite a thermostat performing these two functions, it is to be understood that I intend to cover generically a single thermostat with multiple contacts, ora compound thermostat, i.e. two thermostats.

Humidistat 73 (appropriately located like thermostat 65) and thermostat 65, both control the water supply to pump 45, either alone being sufficient to turn it on, whereas both are required to turn it olf. Thus the evaporative cooling pad 44 of summer use, isemployed in winter to do the humidifying, and -withoutany rerouting of the air-circuits when changing yfrom summer to winter.

FIGURE 7 shows the wiring diagram of this first variant.

For simplicity the thermostat is shown as two thermostats, 65 and 65'. The reference character 80 indicates a source of low-potential electricity, suitable for control-purposes; and v81 a source of high-potential electricity, suitable for actuating an electric motor. The rnotor of pump 45 is lindicated by `the same reference character and 64 represents the heater. 82 and 83 are relays of any convenient sort, such `as magnetic switches. The two thermostats, each acting through its relay, respectively turn on and olf pump 45 yand heater 64, as already explained. Humidistat 73 is in parallel with thermostat 65, in the line of control of pump 45.. This parallel hookup turns on pump 45 if either the thermostat or the hurnidistat is closed, but requires both to be open to turn olf the pump. If desired, each could have its own relay,

the switches of the two relays being in parallel.

FIGURE 7 :is equally applicable to the third to fifth variants, as to first variant.

4 and the pump is on, can be readily understood from Patent No. 2,464,766.

The operation of my apparatus when the heater is oi and the pump is intermittently on and olf, can be readily understood from my copending Patent No. Y2,499,411.

There will now be explained the winter operation of this third variant, when heater `64 is on steadily or intermittently, and pump `45 is not kept on by thermostat 65, but instead is kept on intermittently by hurnidistat 73 just enough to supply the requisite humidioation.

First, however, let us see why heat-exchangepad 3S which is anhydrous when used to cool the hot incoming air in summer7 nevertheless serves to humidity as well as heat the cold incoming air in winter. Inasmuch as each particle of heat-exchange pad 35 is warmed up in its passage across the outgoing air, and is cooled down in its passage across the incoming air, it stands to reason that each particle must be cooler 'than the outgoing air when in contact-therewith, and warmer than the incoming air` when in contact therewith.

If the incoming air is-cold enough, and the outgoing air, when it reaches heat-transfer pad 35, is humid enough, due to its natural moisture content when leaving the room plus whatever moisture is added to it by evaporative pad 44 under the inluence of lthe hurnidistat, this outgoing air in passing through heat-transfer pad 35 will eventually reach a lamina =where it has cooled-down sufficiently to be saturated: i.e., its temperature has reached its dewpoint. Further cooling is impossible without reduction of dewpoint falso. Accordingly, as the outgoing air is cooled to a progressively lower temperature while passing through this pad, it will give up moisture to the remaining laminae `off the pad. Each particle of these laminae, being cooler than the dewpoint temperature of this air, will hold the moisture, until that particle passes into the incoming airstream and meets the incoming air, which being unsaturated and a lower vapor-pressure than the water on the lamina, quickly absorbs'that water. Thus it will be seen that up to a certain lamina this pad, which is an anhydrous heattransferer in summer, transfers sensible heat `anhydrously in winter too, and beyond that lamina transfers both sensible heat and moisture. This same explanation holds Ifor the moisture-exchange part of the cycle of each of the variants to be discussed hereinafter.

The Vdiscussion of the operation of each of the variants is, of course, predicated on the assumption that the capacity of its elements is sufficient.

The Winter operation is as follows. Cold dry outside air enters the apparatus, and `first has its temperature raised considerably by heat-exchange pad 35, `and may also have its moisture content raised thereby to the extent that moisture has been extracted by a part of this pad from the outgoing air, as already explained earlier herein. The temperature of the `air is then further raised, by heater 64, to a temperature controlled by thermostat 65. The air then enters the room 39, where it is mixed with p air already inthe room. The mixture can be expected to lose temperature by the escape of heat to the cold outdoors, and to gain a little moisture. Air leaves the room.

AIn evaporative pad 44 (now acting as a humidilier, if this pad is operating under the influence of hurnidistat 73) the outgoing lair adiabatically loses sensible heat, Iand gains moisture to the extent necessary to cause the incoming air The operation of my apparatus when the heater is off, 75 Let us now consider the second variant of my present invention, which second variant isexernpliiied by FIG- URES 2 and 6. l

Referring to these two figures, we see that they are identical to the variant of FIGURES 1 and 7, except for the following changes. In the upper air-passage, that is to say the incoming air-passage 34, between heat-transfer pad 35 and heater `64, there has been added a second evaporative pad 66. This pad 66 is kept moistened by pump 67 Vdrawing water from tank 46 through pipe 68,

and delivering its water through pipe 6L to trough 70, whence the water seeps do-wn through pad 66. So much of this water as does not evaporate into incoming air dur- 'inng the waters downward seeping through pad 66, is

pad 44 will not function. ,But if the incoming air is cold enough, and the outgoing air is humid enough, the outgoing' air will cool down sufficiently, part way through heat transfer pad 35 to become saturated, and thus (as in the iirst variant) will impart some moisture (via this pad) to the incoming air. If this moisture is not sufficient to produce the humidity `for which the humidistat is set, the humidistat will start pump 67 supplying Awater to evaporative pad 66, which will adiabatically humidify .and cool the incoming air. Heater 64 will supply the heat necessary to compensate this additional coolness. kIf steady operation of pump 67 produces toomuch humidiication, this pump ywill operate intermittently as did pump -45 in the discussion of the first variant.

Let us now consider the third variant of my present invention, as exemplified by FIGURES 3 and 7.

Turning to FIGURE 3, we see that it is identical to FIGURE l, except for the fact that this third variant of mine adds the possibility of recirculation. Dampers 74, n

75, and 76, when properly set, provide this recirculation. Thus, when damper 75 is shut, and the other two dampers are wide open, we have'no recirculation at all, and the variant now under discussion acts exactly like the first variant. But, when damper 75 is wide open, and the other two dampers are shut, we have 100% recirculation. Normally the present variant will operate with the three dampers so adjusted as to attain some intermediate percentage of recirculation, with make-up air being admitted from outdoors through damper 74, and waste air being discharged through damper 76.

When recirculation is employed,` this of course results, dependingupon the percentage of recirculation, in more or less preheating and prehumidifying the incoming air, even to the extent of 'sometimes rendering unnecessary thehumidifying of the incoming air `by means of humidistate 73, evaporative pad 44 andheat-transferrer 35, as explained under variant 1. A small amount of recirculation can result in greatly reducing the heat and moisture load on the heat-transfer wheel. Y

Let us now consider the fourth variant of my present invention, as exempliiied byFIGURES 4 and 7.

Turning now to FIGURE 4, we see it is identical to FIGURE 1, except that in this present variant heater 64 is located in the outgoing air-stream between evaporative pad 44 and heat-transfer pad 35, instead of being (as in the first and third variants) in the incoming stream between heat-transfer pad 35 and room 39.

Lso

. (g warmer than the outdoors air) by evaporative pad 44, under control of humidistat 73;, and then a considerable amount of this moisture and heat is transferred to the incoming air by transferrer 35; the balance of the heat required'by thermostat 65' being then imparted by heater 64 directly to the incoming stream. Whereas in variant 4, after the outgoing air has been humidiiied adiabatically by pady 44, under control of humidistat 73, it is then heated underV control of thermostat 65', and then trans- -mits the required moisture and heat, via transferrer 35,

to the incoming air.

Let us now consider the fifth and final variant of my present invention, which fth variant is exemplified by FIGURES 5l and 7. Y

Turning now to FIGURE 5, we see that it is identical to FIGURE 4, except that in this present variant, heater 64, although still in the outgoing rather than the incoming stream, is now located between room 39 and evaporative pad 44, instead of being (as in the fourth variant) between this pad andheat-exchange pad 35; also recirculation is provided.

This location of heater 64 is very useful, as it enables this present variant to share with variants 1 to` 3 the advantage that a conventional heating unit can be combined with the thermostat-controlled summer anhydrous cooler of my copending Patent No. 2,499,411 (even placing the two at some distance from each other), by the mere Iaddition of appropriate ducts connectingfthe two units, and a humidistat, and appropriate controls, either with or without a set of three dampers to permit and control recirculation of some of the exhaust air.

Moreover this present fifth variant has the following further advantage over even variants 1 to 3, namely that the heater can be located in a heat-closet on the main floor of a house, the bottom panel of which closet is a set of louvers through which passes all the return air from the house. Many houses are being so constructed nowadays and have their heating unit already located in such a closet, and therefore could easily be converted my fifth variant.

Consider now this fifth variant with zero recirculation. Its winter operation differs from that of variant 4; merely that the outgoing air is heated before, rather than after, being humidiiied. Under the same setting of humidistat and thermostat, transferrer 35 should transfer the same amount of moisture and sensible heatV in either of these two variants, within their'respective capacities. But it should be noted that the fifth variant, by heating the outgoing air before rather than after its passing through evaporative pad 44, enables the outgoing air to pick up, and hence have available for transfer by transferrer 35, more moisture than in the other variants. Thus variant 5 is especially adapted to uses in which a high humidity needs to be maintained in the room. f

The discussion of recirculation under the third variant applies equally to this'fifth variant.

Many subvariants of the above Ydescribed live variants are possible without departing from the spirit of my invention. e

Having now described the operation of each of variants 2 to 5, largely by pointing out differences between each of my-fivevariantsand each other, let us now consider their similarities.

It should by now be evident that I have not merely aggregated a heater for winter use with la cooling device for summer use. For, in the first place, I have inserted a heater in a veryk special class of summer coolers. And,

The winter operation differs from that-'of variant 1 as f follows;A In variant 1, the warmhumid air leaving the room is further humidified adiabatically (although still kin the second place, even in that very special class lof the air-streams, to transfer heat in the reversedirection,

namely from the waste air into the incoming air, and (in all of the variants under certain conditions) to transfer moisture as well. For an anhydrous summer heat-exchanger to become a moisture-exchanger in winter, is quite an invention per se.

Then too, the same thermostat which in summer automatically regulates the cooling of the waste air, and thereby the temperature of the incoming fresh air, and thereby the temperature of the room, in winter `automatically regulates the heating of the incoming air, directly in some variants, and in other variants indirectly by heating the waste air, and then transferring this heat to the incoming air.

Furthermore the same summer thermostatic control of the evaporative cooling (but now, in all but one variant, counter-controlled by a humidistat) controls in winter the same evaporative cooling `device but, Without change, now serving to humidity rather than to cool. This counter-controlling of thermostat byhumidistat is another important invention per se. Y

The net result of' all this carefully thought out interaction of an unchanged summer cooler with the minimum of added winter elements, is that my universal air-conditioner operates Winter and summer without rerouting of air or other change-over; and especially that it makes possible a nearly 100% recirculation of the heat of the waste air, with little or no recirculation of the waste air itself.

This recirculation of heat without recirculation of air is the meat of my present invention. It renders my invention particularly useful in crowded spaces, such as theaters, restaurants, hospitals, etc., where it provides easy and inexpensive elimination of the problems of odors and germs, which problems arise from too much recirculation of air.

All five of the herein disclosed variants are inherently capable of transferring moisture by means of the heattransferrer, when necessary to humidify the incoming air.

Having now described iive variants of my invention, I wish it to be understood that my invention is not to be limited to the specific forms or arrangements ofparts herein described and shown.

What is claimed is:

r 1. In combination with a device for Aanhydrously cooling an enclosure, which device includes a first air-passage, for admitting outdoors air to the enclosure, and a distinct second air-passage, for conveying exclusively air exhausted from the enclosure and for discharging the r same, and means for impelling air through these two passages respectively, and means for evaporatively cooling the outgoing air in the second passage, and means to supply water to said evaporative means, and mean for anhydrous heat-exchange `betweenthe air in the two `passages outdoorward of the evaporative means, said heatchange means comprising sectors of air-permeable nonhygroscopic highly heat-absorbent material and means to bring each sector successively into heat-exchange contact with each of the two `air-streams; the combination therewith of means for rendering the device universal, so that the device may be used to heat as well as cool the entering air, such means comprising: a heater in one of the two passages indoorward of the heat-exchange means; 'a thermostat responsive to dry-bulb temperature of air treated by the device; means controlled by said thermostat to turn the heater on in response to air at the thermostat attaining a predetermined minimum drybulb temperature, and to turn the heater off in response to said air attaining a predetermined maximum dry-bulb temperature; and means controlled by the thermostat to reduce the supplying of water to the evaporative cooling means in response to the air at the thermostat attaining a predetermined minimum dry-bulb temperature, and to restore the full supplying of water in resp-onse to said air attaining a predetermined maximum dry-bulb temperature, the two predetermined minima-not necessarily being the same, and the two predetermined maxima vnot necessarily being the same, Ameans for recirculatinga portion of the outgoing `air from the outlet passage into the inlet passage, a humidistat responsive to the moisture content of air treated by the device, and means controlled thereby, to increase the supplying of water to the evaporative means in response to the air at the humidistat attaining a predetermined minimum dew-point, `and to reduce the supplying of water to the evaporative cooling means in response to said air attaining a predetermined maximum dew-point; and interlocking control means between the thermostat, the humidistat, and the water supply means, for independently increasing the supplying of water in response to high temperature or low humidity, and dependently decreasing the supplying of water in response to low temperature and high humidity.

2. In combination with a device for anhydrously cooling an enclosure, which device includes a rst air-passage, for admitting outdoors air to the enclosure, and a distinct second air-passage, for conveying exclusively -air exhausted from the enclosure and fon-discharging the same, and means for impelling air through these two passages respectively, and means for evaporatively cooling the outgoing air in the second passage, `and means to supply water to said evaporative means, and means for anhydrous heat-exchange between the airin the two passages outdoorward of the evaporative means, said heatexchange means comprising sectors of air-permeable nonhygroscopic highly heat-absorbent material and means to bring each sector successivelyinto heat-exchange contact with each of the two air-streams; the combination therewith of means for rendering the device universal, so that the device may be used to heat as well as cool the entering air, such means comprising: a heater in one of the two passages indoorward of the heat-exchange means; a thermostat responsive to dry-bulb temperature of .air treated by the device; means controlled by said thermostat to turn the heater on in response to air at the thermostat attaining a predetermined minimum drybulb temperature, and to turn the heater oif in Vresponse to said air attaining a predetermined maximum dry-bulb temperature; and means controlled by the thermostat to reduce the supplying of water to the evaporative cooling means in response to the air at the thermostat at-j taining a predetermined minimum dry-bulb temperature, and to restore the fully supplying of water in response to said air attaining a predetermined maximum Vdry-bulb temperature, the two predetermined minima not necessarily being the same, and the two predetermined maxima not necessarily being the same, means to render inoperative the control of the water supply to the evaporativecooling means by the thermostat, said -means comprising a humidistat responsive to the moisture content of air treated by the device, and means controlled thereby, to increase the supplying of water to the evaporative cooling 'means in response to the air at the humidistat attaining a predetermined minimum dew-point, and to reduce the supplying of water to the evaporative cooling means in response to said air `attaining a predetermined maximum dew-point; and interlocking control means between the thermostat, the humidistat, and the water supply means, for independently increasing the supplying of water in response to high temperature or low humidity, and dependently decreasing the supplying of Waterin response to low temperature and high humidity; `and further characterized by the fact that there is means for recirculating a portion of the outgoing air from the outlet passage into the first passage.

3. An air-conditioning device according to claim 2, further charactcrized by the fact that the heater is in the second passage.

4. An air-conditioning device according to claim 3, further characterized by the fact that the heater is in the 9 10 second passage, upstream from the evaporative cooling 1,762,320 Wood Juno` 10, 1930 means. 2,468,626 Graham Apr. 26, 1949 2,474,304 Clancy June 28, 1949 References Ciedvin the file of this patent 2,499,411 Pennington Man 7, 19150 UNITED STATES PATENTS 5 2,723,837 Pennington Nov. 15, 1955 1,409,520 Bird Mar. 14, 1922 

